Tilted roller caster

ABSTRACT

The present invention relates to casters of the type in which a roller is rotatably mounted on an axis disposed at an angle of 45* with respect to the vertical and is concerned primarily with certain improvements which improve the service usage and characteristics of such a caster.

United States Patent Closa Feb. 15, 1972 [S4] TILTED ROLLER CASTER 2,978,277 '4/1961 G audry ..16/63 PW [72] Inventor: Just elm, Barcelona, Spain 2,170,257 8/1939 Andersen ..16/31 [73] Assignee: Super Caster Corporation, Miami, Fla. FOREIGN PATENTS 0R APPLICATIONS 4 894,763 4/1962 Great Britain ..16/l8 A [22] 1969 1,114,244 5/1968 Great Britain. 16/45 [21] App], N 791,577 993,928 6/1965 Great Britain .16/18 A Related US. Application Data Primary Examiner-Bobby R. Gay Asnlstam Examiner-Doris L. Troutman [63] Contmuatlon-ln-part of Ser. No. 740,658, June 27, Atomey scheuin and m [57] ABSTRACT B60, The present invention relates to casters of the type in which a mm" is mummy mounted on an axis di at an ans'e of [58] Fieldoiseareh ..16/18A,45,43,46, 18,31, with respect to the vertical and is ncemed primarily 16/39 38 with certain improvements which improve the service usage and characteristics of such a caster. [56] References Cited UN1TED STATES PATENTS 5 Claim, 12 Drawing Figures 2,631,328 3/1953 Kramcsak, Jr ..16/43 PATENTEUFEB 15 m2 SHEET 1 OF 4 JOSE CLOSA BY &@ WW

ATTORNEY PATENTEDFEB 1 5 I972 SHEET 2 [IF 4 INVENT OR JOSE CLOSA A ATTORNEY PATENTEBFEB 15 I972 SHEET 3 [IF 4 INVENTOR JOSE CLOSA I ATTORNEY PATENTEDFEB 15 I972 SHEET t Of 4 INVENTOR JOSE CLOSA ATTORNEY TILTED ROLLER CASTER The application is a continuation-in-part of application Ser. No. 740,658 filed on June 27, I968.

The form of a caster of the type with which this invention is concerned ordinarily includes a metallic main frame in the form of a U with one leg longer than the other and bent back upon itself to form an angle of 45 with the unbent portion. A casing of plastic or comparable material covers the two portions of the bent leg, the back of the U-frame, and presents a downwardly opening housing defined by a top wall and a cylindrical skirt into which the shorter unbent leg extends. The upper part of the bent leg carries means for securing the caster to a piece of furniture while a roller is rotatably mounted on the unbent leg with the upper portion of the roller being located within the housing in overlapping relation therewith. i

The roller may be of a metal such as aluminum but preferably is of a plastic having required properties of strength, elasticity, flexibility and hardness such as nylon. In structure it comprises a central core or hub member that receives the unbent leg of the U-frame, a circular end wall integral therewith, a bevelled or rounded corner structure in tegrally joined to the end wall, a cylindrical wall integral with the corner structure, and a spider supporting said corner structure from the hub and bottom.

In use the roller rolls on its bevelled or rounded edge. This means it rotates relative to the frame leg and housing. There is a strong possibility that dirt, dust or other foreign matter will enter into the space between the skirt of the housing and cylindrical roller wall. At first glance it might appear that the obvious way to guard against this undesirable condition would be to merely provide a very close fit between these two parts. However, such a close fit would materially increase the frictional resistance to rotation of the roller which would be equally undesirable.

With these conditions in mind, the invention has, as an important object, the provision, in a tilted roller caster of the type noted, of an outwardly extending flange on the roller in the area of the overlap between the roller and housing. In any of several locations which this flange may take it will constitute an effective guard against foreign matter entering into the space aforesaid.

A somewhat more detailed object is to provide a flange of the character aforesaid which is defined by an outer and upper tapered or conical surface. This structural formation readily lends itself to shaping the flange when the roller is of aluminum.

Another object is to provide, in a caster roller of the character indicated, an overhanging flange defined by upper and lower conical surfaces. This form may be readily made when the roller is of nylon.

In the known tilted roller casters the structure presenting the bevelled or rounded corner on which the roller rolls is hard and unyielding. While attempt has been made to remedy this undesirable condition by providing a softer rubber ring at this corner such arrangements have certain inherent defects particularly in requiring an extra part and the attendant possibility of the ring becoming disassembled and lost.

With this factor in mind a further yet highly important object in view is to provide, in a tilted roller caster of the kind noted, a rounded or bevelled corner structure which includes an annular groove opening into the end wall of the roller and which groove defines a thin flexible wall on which the roller rides during use.

From actual usage it has been found desirable, if not absolutely necessary, that the rounded or bevelled corner structure be adequately supported from the end wall and core member of the roller. Moreover this need is emphasized when the groove aforesaid is included. The spiders heretofore provided for this purpose have not proven to be entirely satisfactory.

Thus another object is to provide, the type noted, a roller having a spider comprising six equiangularly spaced webs which support the bevelled or rounded corner from the core and end wall.

in a tilted roller caster of In a modified form of a tilted caster the metallic U-shaped frame is omitted and its supporting function performed by a rigid plastic casing presenting two wells or sockets the axes of which are at an angular relation of 45. One of these wells assumes a vertical position when attached to a piece of furniture. The other receives a tilted roller.

An important object of the present invention-is to provide a new and improved journal connection between the vertical well and the furniture piece. In attaining this end the well is lined with a nylon sleeve having an inwardly extending flange adjacent to its lower end and presenting a retaining shoulder. Its upper end is enlarged to provide a bearing race. A stub shaft is affixed to the furniture piece and is formed with a lower end flange which rides past the sleeve flange and engagesthe shoulder thereon to maintain the assembled relation. An outer flange at the upper end cooperates with the bearing race to maintain bearings therein.

Various other more detailed objects and advantages of the invention, such as arise in connection with carrying out the above noted ideas in a practical embodiment, will in part become apparent, and in part be hereinafter stated as the description of the invention proceeds.

For a full and more complete understanding of the invention reference may be had to the following description and accompanying drawings wherein:

' FIG. I is a side view, partly in section and partly in elevation of one embodiment of this invention as applied to a furniture piece;

FIG. 2 is a vertical section taken about on the planes represented by the lines 2-2 of FIG. 1 and depicting the roller in elevation;

FIG. 3 is a perspective developing the several elements of a complete caster in exploded relation;

FIG. 4 is a section through the roller and associated structure, being taken about on the plane represented by the line 4-4 of FIG. 2;

FIG. 4a is a detailed section taken on an enlarged scale through one wall of the roller illustrating a modified form of the dust guard flange;

FIG. 5 is a detailed perspective of the metallic frame per se;

FIG. 6 is a detailed section through the roller, being taken about on the plane represented by the line 66 of FIG. 4;

FIG. 7 is a view partly in section and partly in elevation of a modified form of caster;

FIG. 8 is a section through the roller and associated structure of the form of FIG. 7, being taken about on the plane represented by the line 8-8 of FIG. 7, with the furniture attaching part shown in elevation;

FIG. 9 is a section through the roller of FIGS. 7 and 8, being taken about on the plane represented by the line 9-9 of FIG.

FIG. 10 is a view partly in section and partly in elevation and particularly depicts the swivel portion of the caster; and

FIG. 11 is a view partly in section and partly in elevation of another embodiment with respect to the swivel portion.

Referring now to the drawings, and first more particularly to FIGS. 1 to 6 inclusive, one embodiment of the invention will be described. A metallic frame is shown in detailin FIG. 5 and identified in its entirety by the reference character F. It is of generally U-shape comprising a leg 10, a back or base 11 joined to the leg 10 by a bend l2, and another leg made up of parts 13 and 14 bent at an angle of 45 with respect to each other. The leg part 13 is joined to the back 11 by a bend l5. Adjacent its free end the leg 10 is formed with an annular groove 16 and a similar groove 17 is formed in the leg part 14 adjacent to its free end which may be rounded as illustrated.

A piece of furniture of the type which is provided with casters is shown in FIGS. 1 and 2 and designated 18. In most instances it will be of wood. It has an underface 19 into which opens a socket 20. This socket may be of any cross section but in a preferred embodiment it is square as illustrated.

An anchor plug is referred to in its entirety by the reference character A (FIGS. 2 and 3). It is preferably of plastic and comprises a body 21 having an outer contour corresponding to the shape of the socket 20. Thus it is square. This body 21 has a small flange or bead 22 which fits within the lower open end of the socket that is slightly enlarged for its reception. The body 21 is securely affixed to the piece 18 within the socket 20 as by glue shown at 23. The body 21 is formed with a cylindrical bore 24 that is counterbored at its opposite ends as shown at 25 and 26.

A stud 27, preferably of metal is snugly received in the bore 24 and its lower end projects below the counterbored end 25 of the body 21. It is formed with an auxiliary socket 28 that is shaped and dimensioned to receive the leg part 14 of the frame F. An expansion split spring ring 29 is received in the groove 17 and serves to maintain the stud 27 assembled in the auxiliary socket 28.

A plastic housing is identified in its entirety by the reference character H. It comprises a portion 30 that encases the leg parts 13 and 14 of frame F, a part 31 (FIG. 3) that houses the back 11, and a domelike portion 32 which receives the leg 10 and the upper portion ofa roller to be mounted thereon.

The housing part 32 has a downwardly extending boss 33 (FIG. 4) through which the leg 10 passes and extends therebelow. It also has an outer skirt 34 presenting an inner cylindrical surface 35.

A roller is identified in its entirety by the reference character R. It may be of any material having desired properties of strength, hardness, flexibility and wear resistance. Thus it may be of metal such as aluminum or a plastic such as nylon. In the form of FIGS. 1 to 6 it is shown as being of nylon.

The roller R has an end wall 36 from which upstands a central core 37 defining a cylindrical recess 38 in which the frame leg 10 is journaled. A split ring expansion spring 39 in groove 16 maintains the assembled relation of roller R on leg 10. Also upstanding from the end wall 36 is an outer cylindrical wall 40 that is dimensioned to be loosely fitted in the skirt 34, being spaced from the inner surface thereofas shown in FIG. 4.

In the zone in which the skirt 34 and wall overlap or interfit the latter is formed with an outwardly extending flange 41 which just about engages the surface 35 whereby it functions as a guard to prevent dirt, dust, or other foreign matter from entering the dome housing part 32.

Referring for the moment to FIG. 4a a slightly modified form of dust guard flange is therein depicted. Thus the wall 40 is provided with an overhanging undercut flange 42.

At the peripheral edge of the end wall 36 where it is joined to the wall 40 the outer surface is bevelled or rounded, or a combination of the two as shown at 43. In use the roller R rides or rolls on this surface 43 which engages the floor surface 44.

Extending for an appreciable distance from the end wall 36 is a thickened wall structure 45 and this thickened wall is formed with an annular groove or recess 46 which opens on to the outer surface of the end wall 36. The presence of this groove 46 results in a thin wall or lip 47 which is more flexible and yieldable than is the remaining roller structure. This flexible lip 47 provides better riding action as the roller R rolls over the floor 44.

Referring now more particularly to FIG. 6 six webs 48 are shown as extending between the wall 40 and the core 37. These webs lend strength and rigidity to the roller structure. The core 37 may be formed at its upper end with a pair of diametrically opposed tabs 49 which are received in a groove 50 formed in leg 10. This arrangement aids in the function of maintaining the roller R assembled on the leg 10.

A modified embodiment of the invention is illustrated in FIGS. 7, 8 and 9. In this form a housing designated generally I-I provides the sole structural support between the tilted roller and the part affixed to the furniture piece. Thus the housing H comprises a well structure 51 at one end and a downwardly opening domelike well or socket structure 52 at the other end with the two being joined by a back corresponding to the back 30 of the forms of FIGS. 1 to 6. This housing H may be of any material such as metal or plastic.

Referring now more particularly to FIG. 7 a furniture piece is shown at 53. It has an underface 54 to which the caster is secured by a bracket 55 and wood screws 56. The bracket 55 has an offset central portion 57 which accommodates a head 58 on a stud 59 that passes through an aperture in the offset portion 57.

The stud 59 has an external flange 60 adjacent the socket portion 57 and a curved portion 61 immediately therebeneath. From this curved portion 61 a shank 62 extends to a conical part 63. Below the latter is a cylindrical portion 64 terminating in an end flange 65 presenting an abrupt shoulder 66.

The well structure 51 is formed with a cylindrical socket 67 that is enlarged at 68 with a shoulder 69 between the two, a sleeve 70 of a plastic having good bearing properties such as nylon has an upper enlarged cuplike portion 71. The inner surface 72 of the latter is joined to an annular shoulder 73 by a rounded comer 74. These surfaces 72, 73 and 74 cooperate with flange 60 and rounded undersurface 61 to provide a bearing race receiving ball bearings 75.

Projecting into the bore of sleeve 70 is a flange 76 presenting an upper conical or tapered surface 77 and a lower abrupt shoulder 78.

The mode of assembling the stud 59 in the well structure 51 is believed to be obvious. The nylon sleeve 70 is secured in the housing as by a pressed fit. With the bearings in the race the stud 59 is inserted into the sleeve 70 and when the end flange 65 engages the conical surface 77 the nylon sleeve is distorted sufficiently to permit the flange 65 to ride past the flange 76. When this occurs the shoulders 66 and 78 engage to establish the assembled relation. If the stud can be withdrawn. it can be accomplished only with great force.

FIG. 8 depicts a slightly modified form of roller which is designated generally R. It is preferably of aluminum and comprises an end wall 79 and a circular wall 80. The outer surface of the upper end portion of the latter is formed with a conical flange 81 presenting a bottom shoulder 82. This flange 8] acts as a dust guard in the same way as either of the flanges 41 of FIG. 4 or the flange 42 ofFlG. 4a.

The roller R includes a core 83 having a bore receiving a stub shaft 84, the upper end of which is anchored to an inner central boss 85 of the dome housing part 52. An expansion split ring spring 86 received in a groove 87 in shaft 84 secures the assembly.

Where the outer surface of wall 80 joins the bottom surface of end wall 79 a bevel 88 is provided. As shown the recess 46 and accompanying flexible wall 47 of FIGS. 1 to 6 are omitted. If included the bevel 88 would be replaced by a rounded surface comparable to the rounded surface 43 of FIGS. 1 to 6.

As depicted in FIG. 8 six webs 89 extend between the wall 80 and core 83 to add rigidity to the structure.

In regard to FIG. 10, the main caster of the present invention is connected to a base 90 which may be made of plastic and the like and which has a depending centrally located flange portion 91 adapted to receive a fixed pin 92 by friction fit by a suitable detent as shown. The caster portion is rotatably secured to the pin and rotates thereabout. The caster portion is frictionally fitted to the pin 92 on an extension thereof comprising a plastic bushing 100 constructed of Teflon or the like. To present minimal friction roller bearings 96 in FIG. 10 are annularly arranged about depending flange portion 91 in an annular recess 93 of the caster portion. To further decrease friction, and to act as a thrust bearing, a ball 94 is located between the end of pin 92 and a conically shaped well portion 95 in the caster portion. Annular depending skirt 99 usefully closes off the swivel mechanism.

In FIG. 11 similar structure is shown as in regard to FIG. 10 except that in place of roller bearings 96, a Teflon bushing 97 is disposed. The bushing has an outwardly facing annular groove 98 to contain oil.

The swivel mounts of FIGS. 10 and 11 are capable of taking considerable lateral torque whereby they move about their respective vertical axes for best alignment and consequent movement on the part of the caster. Additionally, the comous modifications of these details may be provided in putting the invention into practice within the purview of the appended claims.

What is claimed is:

1. In a tilted caster including a support presenting a well structure adapted to be secured to a furniture piece in a vertical position and a downwardly opening circular casing having an axis disposed at an angle of 45 with respect to said well structure; means for securing said well structure to a furniture piece, and a roller rotatably assembled in said casing in overlapped relation therewith and having an end wall with a peripheral surface adapted to ride on a floor surface, the improvement consisting of: an outwardly extending flange on said roller in the zone of the overlap with the casing and constituting a guard for preventing foreign matter from entering said casing and wherein the means for securing said well structure to a furniture piece includes a base, said base having an annular depending portion; a stub projecting downwardly from said depending portion; said casing having an upwardly extending portion adapted to mate with said stub to rotate thereabout, said upwardly extending portion having an annular well of a diameter greater than said depending portion, friction reducing means in said well disposed about said depending portion.

2. The tilted caster of claim 1 wherein the friction reducing material is a plastic bushing.

3. The tilted caster of claim 1 wherein the friction reducing material are roller bearings.

4. The tilted caster of claim 1 wherein the mating portion of said stub is plastic and is mated with the casing by means of a friction fit.

5. The tilted caster of claim 4 wherein the mated stub portion has a thrust bearing at the end thereof. 

1. In a tilted caster including a support presenting a well structure adapted to be secured to a furniture piece in a vertical position and a downwardly opening circular casing having an axis disposed at an angle of 45* with respect to said well structure; means for securing said well structure to a furniture piece, and a roller rotatably assembled in said casing in overlapped relation therewith and having an end wall with a peripheral surface adapted to ride on a floor surface, the improvement consisting of: an outwardly extending flange on said roller in the zone of the overlap with the casing and constituting a guard for preventing foreign matter from entering said casing and wherein the means for securing said well structure to a furniture piece includes a base, said base having an annular depending portion; a stub projecting downwardly from said depending portion; said casing having an upwardly extending portion adapted to mate with said stub to rotate thereabout, said upwardly extending portion having an annular well of a diameter greater than said depending portion, friction reducing means in said well disposed about said depending portion.
 2. The tilted caster of claim 1 wherein the friction reducing material is a plastic bushing.
 3. The tilted caster of claim 1 wherein the friction reducing material are roller bearings.
 4. The tilted caster of claim 1 wherein the mating portion of said stub is plastic and is mated with the casing by means of a friction fit.
 5. The tilted caster of claim 4 wherein the mated stub portion has a thrust bearing at the end thereof. 